Memory devices are typically provided as internal, semiconductor, integrated circuits in computers or other electronic devices. There are many different types of memory including volatile and non-volatile memory. Volatile memory can require power to maintain its data and includes random-access memory (RAM), dynamic random access memory (DRAM), and synchronous dynamic random access memory (SDRAM), among others. Non-volatile memory can provide persistent data by retaining stored data when not powered and can include NAND flash memory, NOR flash memory, read only memory (ROM), Electrically Erasable Programmable ROM (EEPROM), Erasable Programmable ROM (EPROM), and resistance variable memory such as phase change random access memory (PCRAM), resistive random access memory (RRAM), and magnetoresistive random access memory (MRAM), among others.
Memory devices can be combined together to form a storage volume of a memory system such as a solid state drive (SSD). A solid state drive can include non-volatile memory (e.g., NAND flash memory and NOR flash memory), and/or can include volatile memory (e.g., DRAM and SRAM), among various other types of non-volatile and volatile memory.
An SSD can be used to replace hard disk drives as the main storage volume for a computer, as the solid state drive can have advantages over hard drives in terms of performance, size, weight, ruggedness, operating temperature range, and power consumption. For example, SSDs can have superior performance when compared to magnetic disk drives due to their lack of moving parts, which may avoid seek time, latency, and other electro-mechanical delays associated with magnetic disk drives.
In various instances, a single level memory cell (SLC) can refer to a cell programmed to a targeted one of two different data states and configured to store a single data unit (e.g., one bit). Some memory cells (e.g., Flash cells, phase change cells, etc.) can be programmed to a targeted one of more than two different data states such that they are configured to store more than a single data unit (e.g., 2 bits, 2.5 bits, 3 bits, 4 bits, etc.). Such cells may be referred to as multi state memory cells, multiunit cells, multilevel cells, or extra level cells (XLCs). XLCs can provide higher density memories without increasing the number of memory cells since each cell can represent more than one data unit.
Various memory cells experience wear over time due to programming and/or erase cycling, for instance. Memory devices comprising such memory cells can have device specifications such as a total bytes written (TBW) specification and/or a cycle count (e.g., erase count and/or program count) specification, for example, used to gauge a device's health and/or useful life. Some memory cells are capable of being operated (e.g., programmed, read, erased, etc.) in both an SLC mode and an XLC mode (e.g., 2-bit “MLC” mode, 3-bit “TLC” mode, 4-bit “QLC” mode, etc.). Such cells can be referred to as “mixed mode” memory cells. Providing accurate device specifications for mixed mode memory devices can be challenging.